
s1_generate_a_series_of_files() {
	for i in {1..100};do echo $i>/tmp/new_file$i;done
}
s2_list_4_files_in_long_format_about_account_and_group() {
	ls -l /etc/{passwd,shadow,group,gshadow} | sort -d
}
s3_find_items_related_to_given_username() {
	grep -h $1 /etc/{passwd,shadow} | sort -d
}
s4_find_items_related_to_given_group_name() {
	grep -h $1 /etc/{group,gshadow} | sort -d
}
s5_create_groups_for_given_group_names() {
	groupadd rnd && groupadd itoperation
}
s6_create_users_and_set_their_group_as_required() {
	useradd -G rnd adam && useradd -G rnd bob && useradd -G itoperation calvin && useradd -G itoperation david && useradd -G rnd edward
}
s7_change_users_shell() {
	usermod -s /usr/bin/sh adam && usermod -s /usr/bin/sh edward
}
s8_set_password_change_policy() {
	passwd -n 10 -x 60 -w 10 adam
    passwd -n 10 -x 60 -w 10 bob
	passwd -n 10 -x 60 -w 10 david
	passwd -n 10 -x 60 -w 10 calvin
	passwd -n 10 -x 60 -w 10 edward	
}
s9_set_password_for_five_users() {
	usernames=(adam bob calvin david edward)
	for i in $(seq 1 5);do echo ${!i};echo $(($i-1));done
	echo "${usernames[0]}:$1" | chpasswd
	echo "${usernames[1]}:$2" | chpasswd
	echo "${usernames[2]}:$3" | chpasswd
	echo "${usernames[3]}:$4" | chpasswd
	echo "${usernames[$(($i-1))]}:$5" | chpasswd
}
s10_lock_bobs_password() {
	usermod -L bob
}
s11_include_adam_into_wheel_group() {
	usermod -a -G wheel adam
}
s12_change_files_permission() {
	for i in {1..33};do chmod -R 640 /tmp/new_file$[3*i];done
}
